Malicious PDF — malware analysis report

Static analysis result for SHA-256 b432afd6d8a6839c…

MALICIOUS

PDF

83.8 KB Created: 2021-09-18 23:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6104301b3474000788bc93f964b97c32 SHA-1: 4c737ef47c550dc34c353172b79809e63e680bf3 SHA-256: b432afd6d8a6839c77ce4495fa82d8bbe6e6b80252a7856d5ceb7dc2ff3281dc
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by multiple heuristics, including a critical ClamAV detection and a high ML score, indicating malicious intent. The presence of an embedded JavaScript stream and a large number of external URIs, many pointing to disposable domains, strongly suggests this PDF is part of a phishing campaign or a downloader for further malicious content. The ML_NYX_PDF_MALICIOUS heuristic with a score of 0.991174 further reinforces the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://oniceh.ru/uplcv?utm_term=how+to+use+sd+card+as+main+storage PDF link annotation
    • https://profm.hu/files/file/fatowaxo.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/rewakudenevidogivari.pdfIn PDF document text
    • http://alarmy-kamery24.pl/userfiles/file/70384817100.pdfIn PDF document text
    • http://prosefkuchare.cz/userfiles/xurefituvesenomozuleguxuw.pdfIn PDF document text
    • http://noticiascgnews.com.br/ckfinder/userfiles/files/bugirubolexilofeveperez.pdfIn PDF document text
    • https://coop-alternatives.fr/images/images/61295083183.pdfIn PDF document text
    • http://sun-marche.com/app/webroot/js/ckfinder/userfiles/files/74466257610.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/19de46b3066ee21265f547ffaca48477/kalofojomexutevux.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16135b9a949206---44021787465.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1631446492.pdfIn PDF document text
    • https://apgr.eu/UserFiles/file/togikudexemupigidomarixav.pdfIn PDF document text
    • https://novamakine.com/upload/ckfinder/files/75314761875.pdfIn PDF document text
    • https://dpt-mh.com/uploads/news/files/gaxebibifetip.pdfIn PDF document text
    • http://modellszerviz.hu/userfiles/file/2614659131.pdfIn PDF document text
    • https://hamzakocakoglu.com/userfiles/file/11997485976.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/dugonigitovutukubuvamok.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/zikogoxakixupipuvujugeguz.pdfIn PDF document text
    • http://a899.net/userfiles/file/63879521763.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/gilegajiwifawiveso.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/44337466811.pdfIn PDF document text
    • https://bem-sa.com/img/file/50051082026.pdfIn PDF document text
    • https://www.larche-de-jules.fr/ckfinder/userfiles/files/fumonilukobixonip.pdfIn PDF document text
    • http://kalikraft.com/images/file/pixixafosonipo.pdfIn PDF document text
    • http://kaies.net/upfiles/file/48419142447.pdfIn PDF document text
    • http://vidol.eu/userfiles/file/vetese.pdfIn PDF document text
    • https://buffinvestment.com/upload/ckfinder/files/10962851787.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF03 19124 bytes
SHA-256: bc7f62d0a9fe09e44565ea8517693a3dea7df9b8364940515ff1f60ff12da27c
font_01_sfnt_off0001100f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1100F 10844 bytes
SHA-256: 85ff340d6f3d78b07d1ae84cc94bd2802041fa2b4e17c4086d6d6c19c448227d
font_02_sfnt_off000128eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1